HOW: Start this exercise upright with both hands in front of you with a resistance band in hands. Spread the resistance band diagonally. Squeeze the band on one end bringing your arm to your side, simultaneously, with the opposite arm elevate the arm in a Y formation (not purely up or across, but in between). Initiate the motion from the scapula and allow the arm to follow this motion.
FEEL: The muscles on the inside of your shoulder blade and on the back of your shoulders.
COMPENSATION: Avoid arching the back and shrugging the shoulder that is lifting up.